An LCD (Liquid Crystal Display) display cannot give out light itself, it needs to be supported by a back light source to realize color-developing in order to see the contents showing on the LCD display clearly. An edge in type back light module is generally composed of necessary optical components such as a light source, a film sheet, a reflector sheet, a light guide plate and a back plate and so on.
A back light unit is an important constituent part of the LCD device, it comprises a back light source and components for installing the back light source, and its structure, assembling, cost and weight are all important technical index. In the existing whole back light unit, the back plate and the sealant frame for holding back light source and (display) panel always play an important role.
The back plate in the traditional back light unit is used for placing the back light source. The light guide plate, optical film sheet and light source are disposed into the back plate, then the sealant frame is pressed onto the back plate to constitute the back light unit. The display panel is disposed on the sealant frame, and then the display panel is buckled to the back light unit by the front frame so as to constitute the back light module. When the light source goes wrong and needs to be replaced, it needs to detach the display panel first, and then detach the back light unit, so that the light source can be replaced. It is easy to destroy the display panel in the changing process, and it is easier to destroy the optical film sheet and the light guide plate in the back light unit, thereby the intrinsic display effect of the display device is destroyed or the resources are wasted.